[ACTIVE][Q] Upgrade and root

Hello
My friend asked me, could i upgrade his Sony Xperia Active. I say YES, but i have one problem. I dont know which ROM will be the newest and which will be the best. Another problem is language. I am from Poland and it will be dificult to find ROM in that language. If there is a ROM which is the newest and it will be in english we will try this. Thx for help.

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